Areas to Watch in Specialty Drug Pipeline Include Cancer, Orphan Drugs

In her presentation at the Academy of Managed Care Pharmacy Nexus 2020 meeting, Aimee Tharaldson, PhD, senior clinical pharmacist of emerging therapeutics at Express Scripts, discussed the upcoming pipeline of specialty drug approvals and their potential impact on the market.

As in past years, we are continuing to see increasing competition in the specialty drug market, which allows for some cost savings, explained Tharaldson. In particular, biosimilars will be important to keep an eye on, as 76 patents will expire from 2020 through 2024, representing $49 billion in opportunity. There are 6 potential biosimilars that could be approved in the remainder of 2020 and in 2021, and each of them could launch upon approval.

An ongoing trend is the increase in drugs approved to treat cancer, as 16 have been approved so far this year and 5 more are expected to be approved by the end of the year, which would break the record of 17 cancer drug approvals set in 2018. Orphan drugs make up a majority of the specialty pipeline, representing the extensive interest in orphan drug development.

As a whole, the specialty drug market is growing, and Tharaldson predicted that 2020 will be the year when specialty drugs account for half of pharmacy drug spending, up from 48% in 2019. This spending will be bolstered by an uptick in specialty drug approvals, with 28 approved so far this year and another 10 expected in the remaining months of 2020.

Tharaldson highlighted the various indications, delivery routes, patient population sizes, and costs of the novel specialty drugs approved so far this year. She also noted some advantages that the newly approved drugs may have over their competitors; for instance, risdiplam (Evrysdi), approved in August for spinal muscular atrophy, costs less than the gene therapy onasemnogene abeparvovec-xioi (Zolgensma) and its oral administration may be preferable to the cerebrospinal fluid injection method of nusinersen (Spinraza).

Next, Tharaldson highlighted the many therapeutic areas where the specialty drug pipeline could yield new approvals in the coming years.

Inflammatory

This is by far the leading class of specialty drugs by per-member-per-year spending, Tharaldson said, and it is dominated by tumor necrosis factor inhibitors. There are 6 upcoming potential approvals in 2021 for a range of inflammatory conditions, featuring both new and expanded indications. For instance, ozanimod (Zeposia) is currently approved for relapsing multiple sclerosis (MS) but could be approved for ulcerative colitis in 2021.

MS

Not many approvals are expected in the near term for MS drugs, with the closest in March 2021 for ponesimod and the rest anticipated from 2022 to 2025. One to keep an eye on is ublituximab, which is expected to offer infusion times of 30 to 60 minutes compared with about 4 hours for the approved ocrelizumab (Ocrevus).

Cancer

By the end of 2020, 5 more cancer drugs could be approved, ranging from biologics to small-molecule drugs to chimeric antigen receptor (CAR) T-cell therapies. Six more have the potential to be approved in the first quarter of 2021, including idecabtagene vicleucel, the first CAR T-cell therapy for multiple myeloma, which is expected to cost around $475,000 for the one-time infusion.

HIV

Strict adherence to HIV antiviral therapy is crucial for viral suppression, explaining why the market is dominated by once-daily regimens. Tharaldson expects 3 approvals in 2021 for HIV therapies, including a cabotegravir/rilpivirine combination, but she said it is unclear how many patients will want to switch from a daily pill to this regimen, in which the rilpivirine is injected monthly by a physician.

Nonalcoholic steatohepatitis (NASH)

This area has been a topic of Tharaldson’s presentations in previous years, as it represents the third-leading cause of cirrhosis and fastest growing cause of liver cancer and liver transplant. Obeticholic acid received a complete response letter from the FDA this June due to its “not very significant” outcomes versus placebo. There are still many drugs in development for NASH, with the earliest approval anticipated in late 2021.

Despite the large potential market, there are many unknowns surrounding the drugs’ long-term clinical benefit, their high cost estimates that will only increase if combination therapies become the standard of care, and unclear diagnosis of NASH and determination of the drugs’ efficacy. Tharaldson estimated it would take a year or two before NASH drugs begin to impact the market.

Alzheimer disease

Current treatment options for Alzheimer disease address symptoms, but disease-modifying drugs represent a “high-risk area of development,” Tharaldson said, as each one so far has failed. Aducanumab, which met its primary study end point, will be reviewed by an FDA advisory panel on November 6. Analysts give this anti–amyloid beta antibody a 30% to 50% chance of approval. On the other hand, hopes for the success of anti-tau antibody therapies for Alzheimer disease have diminished, pushing their market potential back a few years.

High cholesterol

In the hypercholesterolemia space, inclisiran is a small-interfering RNA treatment that could be approved this December, although it is unclear whether it will be considered a specialty drug. Evinacumab, a breakthrough therapy for homozygous familial hypercholesterolemia, could be approved in February.

Duchenne muscular dystrophy

The pipeline for this rare disease includes casimersen, which could be approved in February 2021, as well as 3 gene therapies could potentially be curative in the wider population with the disease regardless of gene mutations. However, it is still unclear how long the effect of the gene therapies could last.

Hemophilia

Tharaldson noted several novel drugs in the pipeline for this area, including one-time infusion gene therapies, which could cost as much as $3 million per treatment but may still be cost-effective if they decrease the need for repeated administration of clotting factor over the long term. Most of the approval actions in this space are targeted for 2022, and there are 2 subcutaneously administered therapies that would be indicated for both hemophilia A and B.

Speaking more broadly about the pipeline of gene therapies, Tharaldson noted that there are 8 potential candidates that could be approved between now and the end of 2021: 3 CAR T-cell therapies, 2 immunotherapy injections for cancers, and 3 gene replacement therapies. Another exciting area is orphan drugs, where there are 6 breakthrough therapies pending approval in the next year, including lonafarnib for the rare fatal condition progeria, lumasiran for primary hyperoxaluria type 1, and vosoritide for achondroplasia.